How many more will have to die as Asia gets hotter?

Record-breaking temperatures, devastating floods, raging bush fires and thousands of deaths. And this might just be the beginning.

With Hong Kong and much of Asia experiencing unusually hot temperatures in the past few months, scientists have warned that heatwaves will become more frequent and more lethal.

“Climate change has played an important role in the occurrence of heatwaves,” said Fu Cheung Sham, chief experimental officer at the Hong Kong Observatory. “As climate warms, the chances of extreme heat will correspondingly increase.”

The World Health Organisation estimates that by the 2030s heat-related deaths in the Asia-Pacific’s high income countries may rise by 1,488, and by more than 21,000 across the entire Asian continent. On a global scale, rising temperatures are expected to cause around 250,000 additional deaths per year between 2030 and 2060, through heat exposure, tropical disease, undernutrition and diarrhoea.

A recent study in the journal PLOS Medicine described how the increase in frequency and severity of heatwaves would trigger a dramatic spike in heat-related deaths across the world, especially if carbon emissions are not checked.

The average number of heatwave-related deaths in Japan, which currently stands at more than 2,000 per year, might jump 170 per cent between 2030 and 2080. That is in a worst-case scenario with rising carbon emissions, growing populations and no public policy measures.

Under the same assumptions, the Philippines might see an increase of more than 1,300 per cent in the number of fatalities provoked by high temperatures. There are currently 322 per year.

But even with lower carbon emissions and better policy preparedness, the study predicted the amount of deaths caused by heatwaves would still increase in most of the 20 countries examined.

During the 15-day heatwave that hit Hong Kong in May, temperatures in subdivided flats and cage homes were recorded as between one and five degrees higher than outdoors, with one home in Yuen Long reaching 42 degree Celsius, according to the Society of Community organisation, a local NGO.

About a third of respondents to a questionnaire by the organisation said they were feeling sick more often because of stifling heat, and 22 per cent experienced symptoms of depression.

Elsewhere in Asia, it has been even worse. The Korean peninsula has been gripped by extreme heat since mid-July, pushing the mercury to an all-time high of 40.7 degrees Celsius in the South Korean city of Hongcheon. The heatwave has caused at least 42 deaths so far.

The North, which has a high incidence rate of malnourishment and is secretive about those numbers, has said it is suffering “an unprecedented natural disaster” that is destroying its crops.

In Japan, torrential rains recently triggered floods and landslides in the southwest, leaving more than 200 people dead, before a heatwave saw temperatures rise to a record-breaking 41.1 degrees, leaving another 80 dead.

In Vietnam, temperatures above 40 degrees in northern and central parts of the country have raised energy consumption to an all-time peak usage rate of 725 million kWh.

Meanwhile, drought has affected up to 40 per cent of inner Mongolia, in northern China, in recent months, causing a plague of rats in its sprawling grasslands. According to Xinhua, the region saw a 25 per cent reduction in rainfall during the second half of June while temperatures rose about 1 degree.

Though not all these events can be attributed to climate change, a study from Oxford University determined that climate change “doubled the likelihood” of such events.

“What was once regarded as unusually warm weather will become commonplace – in some cases, it already has,” said Friederike Otto, from the university’s Environmental Change Institute.

And it’s not just the heat. A study by the Asian Development Bank found that tropical cyclones like Haiyan, which left more than 6,000 dead in the Philippines in November 2013, are becoming stronger due to the increase of sea surface temperatures.

Fu, of the Hong Kong Observatory, predicted “more hot nights and very hot days but fewer cold days; more high heat stress days with longer duration; more frequent extreme rainfall; rising mean sea levels with an increasing threat of storm surge brought about by tropical cyclones”.

As the impacts of global warming become more pronounced across the globe, governments are being forced to find new ways to protect their citizens.

“Climate change is already causing heatwaves, flooding and a more unpredictable monsoon in India,” said Nehmat Kaur, senior manager of The Climate Group, an NGO working with governments and businesses to fight climate change.

Kaur assisted the local government of Ahmadabad in western India to develop a Heat Action Plan after a heatwave in May 2010 left more than 1,300 dead.

The initiative includes an alert system to warn citizens about extreme weather, the creation of water stations in poor neighbourhoods and the erection of outdoor structures to provide shade. Since its implementation in 2013, more than 300 Indian cities have adopted similar plans. Despite these efforts, scientific research suggests weather-related problems are set to intensify.

According to a study by the World Bank, without a cut in carbon emissions, more than half of South Asia will become “hotspots”, or areas in which changing weather will trigger a decline in living standards by 2050.

And even under a scenario in which carbon emissions are reduced, up to 375 million people would still see their living standards drop over the next three decades.

In a recent study, the Massachusetts Institute of Technology concluded that global warming might turn the North Plain region of China, currently home to 400 million people, into an unlivable region.

The report says that by the end of the century the region, which spans five Chinese provinces, would face heatwaves so severe they could kill even healthy people within hours. Researchers hope that recent extreme weather events will be a call to arms to maintain rising temperatures well below 2 degrees, the main goal of the 2015 Paris Agreement.

Failing to meet that goal would create “unmanageable” consequences, including “unprecedented heat extremes recurring every year” in many Asian countries, and stronger typhoons and rising sea levels threatening many of Asia’s river basins and Pacific islands, say climate change experts.

“All the great work done in the Asia-Pacific region in the last decades lifting millions of people out of poverty is now being threatened by climate change,” says Kira Vinke, from the Potsdam Institute for Climate Impact Research. ■